with the nebuleuses of Messier. 1785 contains the famous catalogue of Flamsteed, with the positions of the stars reduced to the beginning of the year 1784, and which supersedes the use of that immense book. 1786 gives you Euler’s lunar tables corrected; and 1787, the tables for the planet Herschel.  The two last needed not an apology, as not being within the description of old almanacs.  It is fixed on grounds which scarcely admit a doubt, that the planet Herschel was seen by Mayer in the year 1756, and was considered by him as one of the zodiacal stars, and, as such, arranged in his catalogue, being the 964th which he describes.  This 964th of Mayer has been since missing, and the calculations for the planet Herschel show that, it should have been, at the time of Mayer’s observation, where he places his 964th star.  The volume of 1787 gives you Mayer’s catalogue of the zodiacal stars.  The researches of the natural philosophers of Europe seem mostly in the field of chemistry, and here, principally, on the subjects of air and fire.  The analysis of these two subjects presents to us very new ideas.  When speaking of the Bibliotheque Physico-oeconomique, T should have observed, that since its publication, a man in this city has invented a method of moving a vessel on the water, by a machine worked within the vessel.  I went to see it.  He did not know himself the principle of his own invention.  It is a screw with a very broad, thin worm, or rather it is a thin plate with its edge applied spirally round an axis.  This being turned, operates on the air, as a screw does, and may be literally said to screw the vessel along:  the thinness of the medium, and its want of resistance, occasion a loss of much of the force.  The screw, I think, would be more effectual, if placed below the surface of the water.  I very much suspect that a countrymen of ours, Mr. Bushnel of Connecticut, is entitled to the merit of a prior discovery of this use of the screw.  I remember to have heard of his submarine navigation during the war, and, from what Colonel Humphreys now tells me, I conjecture that the screw was the power he used.  He joined to this a machine for exploding under water at a given moment.  If it were not too great a liberty for a stranger to take, I would ask from him a narration of his actual experiments, with or without a communication of his principle, as he should choose.  If he thought proper to communicate it, I would engage never to disclose it, unless I could find an opportunity of doing it for his benefit.  I thank you for your information as to the greatest bones found on the Hudson river.  I suspect that they must have been of the same animal with those found on the Ohio:  and if so, they could not have belonged to any human figure, because they are accompanied with tusks of the size, form, and substance of those of the elephant.  I have seen a part of the ivory, which was very good.  The animal itself must have been much larger than an elephant.  Mrs. Adams gives me an account of a flower found in Connecticut, which vegetates when suspended in the air.  She brought one to Europe.  What can be this flower?  It would be a curious present to this continent.